Research Topics
| E EgelmanSummaryAffiliation: University of Virginia Country: USA Publications
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Publications
Helicity in electron microscopy images-a comment on Wang TF, Chen LT and Wang AH 2008 BioEssays 30:48-56Edward H Egelman
Bioessays 30:791-2. 2008
Actin depolymerizing factor stabilizes an existing state of F-actin and can change the tilt of F-actin subunitsV E Galkin
Department of Biochemistry and Molecular Genetics, University of Virginia Health Sciences Center, Charlottesville, Virginia 22908, USA
J Cell Biol 153:75-86. 2001..All of these states display a high degree of cooperativity that appears to be an integral part of F-actin...- A robust algorithm for the reconstruction of helical filaments using single-particle methodsE H Egelman
Department of Biochemistry and Molecular Genetics, University of Virginia, Health Sciences Center, Charlottesville 22908 0733, USA
Ultramicroscopy 85:225-34. 2000..The method can be applied transparently to structures where Bessel overlap would greatly complicate helical analysis. In addition, the procedure allows for the ab initio determination of helical symmetry, when no prior knowledge exists... - A tale of two polymers: new insights into helical filamentsEdward H Egelman
Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, Virginia 22908 0733, USA
Nat Rev Mol Cell Biol 4:621-30. 2003..General features of polymorphism, cooperativity and allostery that emerge from studies of eukaryotic actin and bacterial RecA raise more general issues about how conserved these filamentous structures have been during evolution... - Actin's prokaryotic homologsEdward H Egelman
Department of Biochemistry and Molecular Genetics, University of Virginia Health Sciences Center, Box 800733, Charlottesville 22908 0733, USA
Curr Opin Struct Biol 13:244-8. 2003..It is possible that the interesting properties of eukaryotic F-actin may account for the unusual degree of conservation among the actins, whereas the bacterial proteins have had fewer constraints over the course of evolution... 
Single-particle reconstruction from EM images of helical filamentsEdward H Egelman
Department of Biochemistry and Molecular Genetics, University of Virginia, Box 800733, Charlottesville, VA 22908 0733, USA
Curr Opin Struct Biol 17:556-61. 2007..Applications of these new methods to viruses, actin filaments, pili and many other polymers show the great advantages of the new methods...- The iterative helical real space reconstruction method: surmounting the problems posed by real polymersEdward H Egelman
Department of Biochemistry and Molecular Genetics, University of Virginia Health Sciences, P O Box 800733, Charlottesville, VA 22908 0733, USA
J Struct Biol 157:83-94. 2007..The problems inherent in the traditional approach are discussed, and examples are presented illustrating how the IHRSR approach surmounts these problems... 
Electron microscopy of helical filaments: rediscovering buried treasures in negative stainEdward H Egelman
Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, VA 22908 0733, USA
Bioessays 31:909-11. 2009..The failure to appreciate this has recently led to an incorrect interpretation of RecA-family filament structures...- Does a stretched DNA structure dictate the helical geometry of RecA-like filaments?E H Egelman
Department of Biochemistry and Molecular Genetics, University of Virginia Health Sciences Center, Charlottesville, VA 22908 0733, USA
J Mol Biol 309:539-42. 2001..In this view, these proteins stabilize this existing state of DNA, rather than induce a novel conformation... - Molecular evolution: actin's long lost relative foundE H Egelman
Department of Biochemistry and Molecular Genetics, Box 800733, University of Virginia Health Sciences Center, Charlottesville, Virginia 22908 0733, USA
Curr Biol 11:R1022-4. 2001..While we still know little about MreB's function, the structural similarities and differences between MreB and actin provide more insight into the remarkable properties of actin... - Reducing irreducible complexity: divergence of quaternary structure and function in macromolecular assembliesEdward H Egelman
Department of Biochemistry and Molecular Genetics, University of Virginia Health Sciences Center, Charlottesville, VA 22908 0733, USA
Curr Opin Cell Biol 22:68-74. 2010..Work on the enzyme FucU, involved in fucose metabolism, may suggest similar conclusions... - Bacterial conjugation: running rings around DNAE H Egelman
Department of Biochemistry and Molecular Genetics, Box 800733, University of Virginia Health Sciences Center, Charlottesville, VA 22908 0733, USA
Curr Biol 11:R103-5. 2001..An integral membrane bacterial protein assembly involved in the transfer of DNA between cells has been shown to resemble a ring helicase, suggesting that it hydrolyzes ATP to pump DNA through a central channel... - The location of ubiquitin in Lethocerus arthrinVitold E Galkin
Department of Biochemistry and Molecular Genetics, University of Virginia Health Sciences Center, Jordan Hill Box 800773, Charlottesville, VA 22908-0733, USA
J Mol Biol 325:623-8. 2003..This might be the basis for a destabilization of the on state at rest length. Lys118 is the most likely residue to which the ubiquitin is conjugated, based upon fitting atomic structures of actin and ubiquitin into the reconstruction... - The bacterial protein SipA polymerizes G-actin and mimics muscle nebulinVitold E Galkin
Department of Biochemistry and Molecular Genetics, University of Virginia Health Sciences Center, Charlottesville, Virginia 22908, USA
Nat Struct Biol 9:518-21. 2002..We suggest that SipA is a bacterial structural mimic of muscle nebulin and nebulin-like proteins in non-muscle cells that are involved in the regulation of the actin-based cytoskeleton... - Actin-destabilizing factors disrupt filaments by means of a time reversal of polymerizationAlbina Orlova
Department of Biochemistry and Molecular Genetics, University of Virginia Health Sciences Center, Charlottesville, VA 22908-0733, USA
Proc Natl Acad Sci U S A 101:17664-8. 2004..These observations suggest that F-actin filaments are annealed over time into a stable filament and that actin-depolymerizing proteins can effect a time reversal of polymerization... - Do the utrophin tandem calponin homology domains bind F-actin in a compact or extended conformation?Vitold E Galkin
Department of Biochemistry and Molecular Genetics, University of Virginia Health Sciences Center, Jordan Hill Box 800773, Charlottesville, VA 22908 0733, USA
J Mol Biol 331:967-72. 2003..We conclude that helical averaging applied to disordered filaments is responsible for their results, and that approaches designed to separate out homogeneous subsets within such filamentous complexes offer many advantages... - Each actin subunit has three nebulin binding sites: implications for steric blockingNatalya Lukoyanova
Department of Biochemistry, University of Virginia, Charlottesville 22908 0733, USA
Curr Biol 12:383-8. 2002..Muscle regulation involves tropomyosin movement on the surface of actin, with binding in three states. Our results suggest the intriguing possibility that intact nebulin may also be able to occupy three different sites on F-actin... - The hexameric ring structure of the Escherichia coli RuvB branch migration proteinYen Ju Chen
Department of Biochemistry and Molecular Genetics, University of Virginia Health Sciences, Box 800733, Charlottesville, VA 22908 0733, USA
J Mol Biol 319:587-91. 2002..This suggests that there may be a highly conserved structure for many proteins involved in different aspects of DNA replication, recombination, transcription and repair... - Structural polymorphism of the ParM filament and dynamic instabilityVitold E Galkin
Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, VA 22908 0733, USA
Structure 17:1253-64. 2009..Our results suggest that the closed state of the cleft is required but not sufficient for ParM polymerization, and provide a structural basis for the dynamic instability of ParM filaments... - Issues of resolution and polymorphism in single-particle reconstructionShixin Yang
Department of Biochemistry and Molecular Genetics, University of Virginia Health Sciences Center, Charlottesville, VA 22908-0733, USA
J Struct Biol 144:162-71. 2003..These averages, however, are themselves artefactual as they involve heterogeneous images. The issues presented here need to be considered when single-particle EM reconstructions are evaluated... - The CH-domain of calponin does not determine the modes of calponin binding to F-actinVitold E Galkin
Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, VA 22908-0733, USA
J Mol Biol 359:478-85. 2006..This has broad implications for inferring function from the presence of structurally conserved domains... - The structure of bacterial ParM filamentsAlbina Orlova
Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, Virginia 22908 0733, USA
Nat Struct Mol Biol 14:921-6. 2007..The present results yield new insights into polymorphisms within F-actin, as well as the evolution of polymer families... - Coronin-1A stabilizes F-actin by bridging adjacent actin protomers and stapling opposite strands of the actin filamentVitold E Galkin
Department of Biochemistry and Molecular Genetics, University of Virginia, Box 800733, Charlottesville, VA 22908 0733, USA
J Mol Biol 376:607-13. 2008..We suggest that the stapling of subdomain 1 and subdomain 4 of two actin protomers on different strands is a common mechanism for F-actin stabilization utilized by many actin-binding proteins that have no homology... - Structural polymorphism in F-actinVitold E Galkin
Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, Virginia, USA
Nat Struct Mol Biol 17:1318-23. 2010..Because F-actin is structurally polymorphic, it cannot be described using only one atomic model and must be understood as an ensemble of different states... - Divergence of quaternary structures among bacterial flagellar filamentsVitold E Galkin
Department of Biochemistry and Molecular Genetics, Box 800733, University of Virginia, Charlottesville, VA 22908 0733, USA
Science 320:382-5. 2008..The driving force in the change of quaternary structure between Salmonella and Campylobacter may have been the evasion of TLR5... - ATP-mediated conformational changes in the RecA filamentMargaret S VanLoock
Department of Biochemistry and Molecular Genetics, University of Virginia Health Sciences, Charlottesville, VA 22908, USA
Structure 11:187-96. 2003..This simple rotation can explain the large cooperativity in ATP hydrolysis observed for RecA-DNA filaments... - The structure of a filamentous bacteriophageYing A Wang
Department of Biochemistry and Molecular Genetics, University of Virginia, Box 800733, Charlottesville, VA 22908-0733, USA
J Mol Biol 361:209-15. 2006..These results show that new computational approaches to helical reconstruction can greatly extend the ability to visualize heterogeneous protein polymers at a reasonably high resolution... - High-resolution cryo-EM structure of the F-actin-fimbrin/plastin ABD2 complexVitold E Galkin
Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, VA 22908 0733, USA
Proc Natl Acad Sci U S A 105:1494-8. 2008.... - A new internal mode in F-actin helps explain the remarkable evolutionary conservation of actin's sequence and structureVitold E Galkin
Department of Biochemistry and Molecular Genetics, University of Virginia Health Sciences Center, Charlottesville, VA 22908, USA
Curr Biol 12:570-5. 2002..Remarkably, we find that in the tilted state actin subunits make new contacts with neighboring subunits that also involve these inserts, suggesting a key role for these elements in F-actin polymorphism... - The Arg non-receptor tyrosine kinase modifies F-actin structureVitold E Galkin
Department of Biochemistry and Molecular Genetics, University of Virginia Health Sciences Center, Charlottesville, VA 22908-0733, USA
J Mol Biol 346:565-75. 2005..The conformational changes in the filament introduced by Arg can explain the cooperative binding of Arg to F-actin and might prevent other actin binding proteins from binding to actin filaments... - Cleavage of bacteriophage lambda cI repressor involves the RecA C-terminal domainVitold E Galkin
Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, VA 22908 0733, USA
J Mol Biol 385:779-87. 2009..Under conditions where the repressor cleavage rates are the highest, cI is coordinated within the groove by contacts with RecA's CTD. These observations provide a framework for understanding previous genetic and biochemical observations... - SV40 large T antigen hexamer structure: domain organization and DNA-induced conformational changesMargaret S VanLoock
Department of Biochemistry and Molecular Genetics, University of Virginia Health Sciences, Box 800733, Charlottesville, VA 22908-0733, USA
Curr Biol 12:472-6. 2002.... - ADF/cofilin use an intrinsic mode of F-actin instability to disrupt actin filamentsVitold E Galkin
Department of Biochemistry and Molecular Genetics, University of Virginia Health Sciences Center, Jordan Hall, Charlottesville, VA 22908-0733, USA
J Cell Biol 163:1057-66. 2003..We suggest that AC proteins use an intrinsic mechanism of F-actin's internal instability to depolymerize/sever actin filaments in the cell... - Opening of tandem calponin homology domains regulates their affinity for F-actinVitold E Galkin
Department of Biochemistry and Molecular Genetics, University of Virginia Medical Center, Charlottesville, Virginia, USA
Nat Struct Mol Biol 17:614-6. 2010.... - Xin-repeats and nebulin-like repeats bind to F-actin in a similar mannerOlga Cherepanova
Department of Biochemistry and Molecular Genetics, University of Virginia Health Sciences Center, Charlottesville, VA 22908-0733, USA
J Mol Biol 356:714-23. 2006..Taken together with published data about nebulin, tropomyosin and ADF/cofilin, our results suggest that the ability to bind in multiple modes to the actin protomer is a general property of many actin-binding proteins... - The utrophin actin-binding domain binds F-actin in two different modes: implications for the spectrin superfamily of proteinsVitold E Galkin
Department of Biochemistry and Molecular Genetics, University of Virginia Health Sciences Center, Charlottesville, VA 22908, USA
J Cell Biol 157:243-51. 2002..The cell may use the modular CH domains found in the spectrin superfamily of actin-binding proteins to bind actin in manifold ways, allowing for complexity to arise from the interactions of a relatively few simple modules with actin... - The stalk region of dynamin drives the constriction of dynamin tubesYen-Ju Chen
Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, Virginia, USA
Nat Struct Mol Biol 11:574-5. 2004..We solved the nonconstricted state by a single-particle approach and show that the stalk region of dynamin undergoes a large conformational change that drives tube constriction... - Structural polymorphism in bacterial EspA filaments revealed by cryo-EM and an improved approach to helical reconstructionYing A Wang
Department of Biochemistry and Molecular Genetics, Box 800733, University of Virginia, Charlottesville, VA 22908, USA
Structure 14:1189-96. 2006..Outside of a crystal, where there is nothing to maintain long-range order, the structural polymorphism in helical polymers may be much greater than has been assumed... - BRCA2 BRC motifs bind RAD51-DNA filamentsVitold E Galkin
Department of Biochemistry and Molecular Genetics, University of Virginia Health Sciences Center, Charlottesville, VA 22908 0733, USA
Proc Natl Acad Sci U S A 102:8537-42. 2005.... - Helical filaments of human Dmc1 protein on single-stranded DNA: a cautionary taleXiong Yu
Department of Biochemistry and Molecular Genetics, Box 800733, University of Virginia, Charlottesville, VA 22908 0733, USA
J Mol Biol 401:544-51. 2010..While three-dimensional reconstruction of helical filaments from EM images is a powerful tool, the intrinsic ambiguities that may be present with limited resolution are not sufficiently appreciated... - The Methanobacterium thermoautotrophicum MCM protein can form heptameric ringsXiong Yu
Department of Biochemistry and Molecular Genetics, University of Virginia Health Sciences Center, Charlottesville, VA 22908, USA
EMBO Rep 3:792-7. 2002..While the structure of the ring is very similar to that of hexameric replicative helicases such as bacteriophage T7 gp4, our results show that such ring structures may not be constrained to have only six subunits... - The structure of the Salmonella typhimurium type III secretion system needle shows divergence from the flagellar systemVitold E Galkin
Department of Biochemistry and Molecular Genetics, University of Virginia Medical School, Charlottesville, VA 22908 0733, USA
J Mol Biol 396:1392-7. 2010..In contrast to the Sa. typhimurium flagellar filament, which shows a nearly crystalline order, the Sa. typhimurium needle has a highly variable symmetry, which could be used to transmit information about host cell contact... - The structure of F-piliYing A Wang
Department of Biochemistry and Molecular Genetics, University of Virginia, Charlottesville, VA 22908 0733, USA
J Mol Biol 385:22-9. 2009..This coexistence of two very different symmetries is similar to what has recently been reported for an archaeal Methanococcus maripaludis pili filament and an archaeal Sulfolobus shibatae flagellar filament... - Complexes of RecA with LexA and RecX differentiate between active and inactive RecA nucleoprotein filamentsMargaret S VanLoock
Department of Biochemistry and Molecular Genetics, University of Virginia Health Sciences Center, Charlottesville, VA 22908-0733, USA
J Mol Biol 333:345-54. 2003..Since RecX binds from the C-terminal domain of one subunit to the nucleotide-binding core of another subunit, a stabilization of RecA's C-terminal domain by RecX can likely explain the inhibition of RecA's ATPase activity by RecX... - Acrosomal actin: twists and turns of a versatile filamentEdward H Egelman
Department of Biochemistry and Molecular Genetics, University of Virginia Health Sciences Center, Box 800733, Charlottesville, Virginia 22908-0733, USA
Curr Biol 14:R959-61. 2004..The twist and tilt of the actin subunits show very large deviations from ideal F-actin, providing clues about actin dynamics... - Structural polymorphism of Methanothermobacter thermautotrophicus MCMYen Ju Chen
Department of Biochemistry and Molecular Genetics, Box 800733, University of Virginia Health Sciences Center, Charlottesville, VA 22908, USA
J Mol Biol 346:389-94. 2005..This offers new insight into the conformational dynamics of MCM and the phosphorylation-bypass phenotype in yeast... - The structure of an archaeal pilusYing A Wang
Department of Biochemistry and Molecular Genetics, University of Virginia, Box 800733, Charlottesville, VA 22908 0733, USA
J Mol Biol 381:456-66. 2008..This result has many implications for understanding the evolutionary divergence of bacteria and archaea... - Flexibility of the rings: structural asymmetry in the DnaB hexameric helicaseShixin Yang
Department of Biochemistry and Molecular Genetics, University of Virginia Health Sciences Center, Jordan Hall, Box 800773, Charlottesville 22908 0733, USA
J Mol Biol 321:839-49. 2002.... - The Rad51/RadA N-terminal domain activates nucleoprotein filament ATPase activityVitold E Galkin
Department of Biochemistry and Molecular Genetics, University of Virginia, Box 800733, Charlottesville, Virginia 22908, USA
Structure 14:983-92. 2006..These results show that the N-terminal domains play a regulatory role in filament activation and highlight the modular architecture of the recombination proteins... - Cell walls, cell shape, and bacterial actin homologsEdward H Egelman
Department of Biochemistry and Molecular Genetics, University of Virginia Health Sciences Center, Charlottesville, VA 22908, USA
Dev Cell 5:4-5. 2003..The synthesis of the peptidoglycan layer, one of the key determinants of cell shape in B. subtilis, has been shown by Daniel and Errington to occur in a helical pattern. This pattern is generated by the actin homolog Mbl... - Assembly of Weibel-Palade body-like tubules from N-terminal domains of von Willebrand factorRen Huai Huang
Howard Hughes Medical Institute, Washington University School of Medicine, St Louis, MO 63110, USA
Proc Natl Acad Sci U S A 105:482-7. 2008..2 units per turn. The symmetry and location of interdomain contacts suggest that decreasing pH along the secretory pathway coordinates the disulfide-linked assembly of VWF multimers with their tubular packaging... - Actin hydrophobic loop 262-274 and filament nucleation and elongationAlexander Shvetsov
Department of Chemistry and Biochemistry and Molecular Biology Institute, University of California, Los Angeles, CA 90095, USA
J Mol Biol 375:793-801. 2008..Our findings show an importance of the hydrophobic loop conformational dynamics in both actin nucleation and elongation and reveal that the inhibition of these two steps in the cross-linked actin can be relieved by appropriate factors... - Salmonella SipA polymerizes actin by stapling filaments with nonglobular protein armsMirjana Lilic
Laboratory of Structural Microbiology, Rockefeller University, New York, NY 10021, USA
Science 301:1918-21. 2003..Deletion analysis of the tethering arms provides strong support for this model... - Refining the structure of the Halobacterium salinarum flagellar filament using the iterative helical real space reconstruction method: insights into polymorphismShlomo Trachtenberg
Department of Membrane and Ultrastructural Research, The Hebrew University of Jerusalem Hadassah Medical School, P O Box 12272, Jerusalem 91120, Israel
J Mol Biol 346:665-76. 2005..Single alpha-helices can be fit into the reconstruction, supporting the proposed similarity of the structure to that of type IV bacterial pili... - A DNA pairing-enhanced conformation of bacterial RecA proteinsNami Haruta
Department of Biochemistry, University of Wisconsin, Madison, Wisconsin 53706, USA
J Biol Chem 278:52710-23. 2003..3) RecA filaments bound to dsDNA (P state) have directly observable structural changes relative to RecA filaments bound to ssDNA (A state), involving the C-terminal domain... - Mapping the interaction of cofilin with subdomain 2 on actinSabrina A Benchaar
Department of Chemistry and Biochemistry, Molecular Biology Institute and Department of Biological Chemistry, University of California, Los Angeles, California 90095, USA
Biochemistry 46:225-33. 2007..Overall, these results demonstrate that the region around Gln41 (subdomain 2) is involved in a weak binding of cofilin to G-actin... - More insights into structural plasticity of actin binding proteinsEdward H Egelman
Structure 12:909-10. 2004 - Homologous-pairing activity of the Bacillus subtilis bacteriophage SPP1 replication protein G35PSilvia Ayora
Departmento de Biotecnologia Microbiana, Centro Nacional de Biotecnologia, Consejo Superior de Investigaciones Cientificas, , Madrid 28049, Spain
J Biol Chem 277:35969-79. 2002..The loading of G40P at a d-loop (ori DNA or at any stalled replication fork) by G35P could lead to replication fork reactivation... - Functional and structural basis for a bacteriophage homolog of human RAD52Mickael Ploquin
Genome Stability Laboratory, Laval University Cancer Research Center, Hotel Dieu de Quebec, 9 McMahon, Quebec City G1R 2J6, Canada
Curr Biol 18:1142-6. 2008..For the first time, we propose a viral homolog of RAD52 at the amino acid, phylogenic, functional, and structural levels... - Atomic model of a myosin filament in the relaxed stateJohn L Woodhead
Department of Cell Biology, University of Massachusetts Medical School, Worcester, Massachusetts 01655, USA
Nature 436:1195-9. 2005.... - A comparative analysis of Dmc1 and Rad51 nucleoprotein filamentsSean D Sheridan
Committee on Genetics, University of Chicago, Chicago, IL 60637, USA
Nucleic Acids Res 36:4057-66. 2008.... - Helical structure of the needle of the type III secretion system of Shigella flexneriFrank S Cordes
Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, United Kingdom
J Biol Chem 278:17103-7. 2003..6 subunits/turn, 24-A helical pitch). This common architecture implies that there will be further mechanistic analogies in the functioning of these two bacterial systems... - Structural basis of membrane invagination by F-BAR domainsAdam Frost
Departments of Molecular Biophysics and Biochemistry, Yale University School of Medicine, New Haven, CT 06510, USA
Cell 132:807-17. 2008..The geometric constraints and sequential assembly of the helical lattice explain how F-BAR and classical BAR domains segregate into distinct microdomains, and provide insight into the spatial regulation of membrane invagination... - How does ATP hydrolysis control actin's associations?Elena P Sablin
Department of Biochemistry Biophysics, University of California, San Francisco, CA 94143, USA
Proc Natl Acad Sci U S A 99:10945-7. 2002 - Structure and function of Hib pili from Haemophilus influenzae type bXiang-Qi Mu
Department of Physiology and Biophysics, Boston University School of Medicine, Boston, MA 02118-2526, USA
J Bacteriol 184:4868-74. 2002..This capacity to resist unwinding may be important for continued adherence of H. influenzae type b to the nasopharynx, where the three-stranded Hib pilus filaments provide a robust tether to withstand coughs and sneezes... - Actin structure and function: what we still do not understandEmil Reisler
Department of Chemistry and Biochemistry and the Molecular Biology Institute, University of California, Los Angeles, California 90095, USA
J Biol Chem 282:36133-7. 2007 - Stabilization of RAD51 nucleoprotein filaments by the C-terminal region of BRCA2Fumiko Esashi
Cancer Research UK, London Research Institute, Clare Hall Laboratories, South Mimms, Herts EN6 3LD, UK
Nat Struct Mol Biol 14:468-74. 2007..We suggest that interactions of the BRCA2 C-terminal region with RAD51 may facilitate efficient nucleation of RAD51 multimers on DNA and thereby stimulate recombination-mediated repair... - RecA assembly, one molecule at a timeEdward H Egelman
Structure 14:1600-2. 2006